Recent Experience in Timing Sprays for Control of Apple Scab: Equipment and Test Results. M. G. Zuck, Assistant Scientist, Department of Botany and Plant Pathology, University of Maine, Orono 04469. W. E. MacHardy, Associate Professor, Department of Botany and Plant Pathology, University of New Hampshire, Durham 03824. Plant Dis. 65:995-998. Accepted for publication 2 March 1981. Copyright 1981 American Phytopathological Society. DOI: 10.1094/PD-65-995.

Two weather monitoring instruments, developed for use in commercial orchards, were used to detect infection periods of apple scab in Maine and New Hampshire. Eradicant treatments using nonregistered fungicides were as effective in controlling leaf and fruit scab as registered and nonregistered protectant treatments. Three sprays were saved using the eradicant spray program. An experimental spore trap, developed for use by growers in detecting Venturia inaequalis ascospores, was tested in a wind tunnel against a recording volumetric spore trap and in three commercial orchards with low inoculum levels. The experimental unit trapped ascospores at about 65% of the efficiency of the recording volumetric spore trap. Ascospores were detected during only one wetness period in each commercial orchard.

Keyword(s): integrated pest management, spore trap.